Hello from Tyne & Wear

Hello to you all. A little potted history before I ask for advice;
I previously owned & have toured in a caravan in the UK, around eight years ago my wife and I toured Europe on a motorbike 2 years running and loved the freedom of it.
A couple of years ago I began to tinker, I restored a couple of motorbikes then bought an old MG Midget for this years project however it's beyond saving. We love camping with the family and friends, took our tent and gear to France last year and had a fab holiday.
We'd talked about my next project being a van conversion, I've read a fair bit about it and feel happy I have the skill to do most of the work and the sense to know which jobs to leave to someone else (I have many a mate with various skills)

My current thinking is to get hold of a Sprinter 312 LWB around 04' '05 with less than 100k on the clock and a damaged caravan for donor parts.
I have a 16 yr old son & we have an 8 yr old daughter so would ideally need it to be 4 berth (hence the LWB) considering that we need a toilet on board so may as well plumb for a shower as well.
Think I'll probably go for the solar panel option to steal the sun's juice and considering whether we need to fit an air con unit to the roof for the Mediterranean heat.

I can guarantee that you will get sick of my sfq's in the coming months so please bear with me and be kind.

First question, even if I insulate the van well (which I plan to) is air con necessary for France/Spain type touring or would shady spot parking do the trick?

Welcome to the madhouse, I'm sure you will enjoy the banter. I'm just outside Durham so I am pretending to be a Geordie (badly). Your mission to convert is very sensible. I have just sourced a very nice LWB Fiat with 40,000 miles. Very clean and fully ply lined so no interior dings. I have decided to have a van converted but I may just sell on. A long time friend of time has been converting vans for over 25 years (full time job) so he makes a first class job. His layouts are to your spec and the final job is very, very good.
I wish you luck with your van search and hope it all turns out well for you.